Shopping centre wars have erupted across Glasgow as retailers step up their competition for the top spot.

Plans to upgrade Buchanan Galleries took a major step forward this week when its £100 million expansion programme was given outline planning approval.

It is a massive boost for the centre as it competes with the massive new Silverburn centre in Pollok and to keep pace with city centre rivals the St Enoch Centre.

The expanded Buchanan Galleries, above, will become one of the largest shopping centres in the UK, measuring 1.3 million square feet.

It will eventually overtake the £350m Silverburn, which stands at 1.1 million square feet, and will include additional retail space, a new atrium entrance on Buchanan Street and bar and restaurant facilities.

A spokesman said: "We believe retailers are looking for good quality city centre space We welcome the other recent investment into the surrounding area which will strengthen Glasgow's position as the best retail destination outside London."

Work is due to finish in 2011 but the plans will need final approval from the Scottish Government. The battle faced by city centre malls to keep up with the changing face of Scottish retail is fierce as St Enoch Centre bosses push ahead with their own £100m expansion programme.

Canadian owners Ivanhoe Cambridge plan to create a new centre of more than one million square feet by 2009, bringing more than 40 new retailers and leisure outlets into the facility.

Braehead Shopping Centre, on the outskirts of Glasgow, is also thriving and managed to attract just under 20 million customers last year.

Owners Capital Shopping Centre are progressing through plans for almost 2000 new homes, a riverside park, 900,000 square feet of new offices and 470,000 square feet of retail and leisure space, including the Xscape centre. Susan Moriarty, director of the Scottish Retail Consortium, said the boom was good news for Scottish shoppers.

She said: "Glasgow and the outlying areas have a fantastic retail offering and Glasgow city centre is the jewel in the crown of Scottish retailing. What we are seeing now is a growth in retail destinations bringing more choice for consumers."

Silverburn boss Richard Low, director of Combined Property, said the shopping centre was leading the way in the retail sector.

He said: "Many other shopping centres in Scotland are now playing catch-up to meet retailers' requirements but Silverburn is the best example of 'next generation' shopping in the UK.

"We have invested £350m and spent 12 years creating Silverburn which captures the excitement, glamour and variety of a city-centre high street with the benefit of larger stores, free parking and direct motorway access. It is good news that Silverburn has sparked investment in retail across Scotl and as it will serve to drive up standards.

"At Silverburn, retailers like Tesco and Next have the space to set up their flagship stores and that's why we are in a very fortunate position."

Bosses at the St Enoch Centre, which officially launched its renovation programme in June, welcomed the increased competition.

General Manager Susan Nicol said: "We see the developments around the city as very positive.

"Competition is stiff, but we welcome that and see it as all about making the city centre stronger.

"I think there is room for everyone in Glasgow as well as for the out-of-town centres like Silverburn.

"People will go to those centres, but hopefully they will also come into the city centre for the different experience that brings."